Railway braking apparatus



l.. V. LEWIS RAILWAY BRAKING APPARATUS Nov. 2., 1926. 1,605,044

Filed Dec. 15. 1925 m m Y L M@ vg @KS n in L-*i y.

INVENTOR'.

i atented Nov. 2, 1926.

STAFF-lullin@ LLOYD 'LE-WIS OF EDG'YVOOD, PENNSYLVANIA., ASSGNOR TO THE UNION SVSTCH a SIGNAL COVIPANY, OE SNISSVALE, ENNSYL'VANA, A CORPORATION 0F ENN- SYLVANIA.

RALWAY BEARING APPARATUS.

Application led December 15,` 1925.

My invention relates to railway braking apparatus, and particularly to apparatus of the type comprising a braking bar located in the trackway and a. motor device for moving such bar into engagement with a part of a railway vehicle. More particularly my invention relates to means for controlling such motor device.

I will describe one form of railway braking apparatus embodying my invention, and will then point out the novel features thereof in claims.

The accompanying drawing is a view partly diagrammatic, illustrating one form of railway braking apparatus embodying my invention.

Referring to the drawing, the reference characte 1 and 1ZL designate the track rails of a stretch of railway track. Located `on opposite sides of rail 1 and extending parallel therewith are two braking bars 2 and 3. Similar braking bars 2EL and 3a entend parallel with rail 1a on opposite sides thereof.

The braking bars 2, 3, 2a and 3 'areoperated by a fluid pressure motor designated in general by the reference character M. This motor comprises a cylinder 5 containing a reciprocable piston 6 to which is attached a piston rod 6a. The braking bars 2, 3, 2a and 3a are operatively connected with the piston rod 6 of motor M through suitable linkage including a lever l pivoted at point 42u. TWhen piston 6 moves to its left-hand position, bars 3 and 8a are moved to the left and bars 2 and 2EL are moved to the right and the bars then occupy their non-braking positions as shown in the drawing. l/Vhen piston 6 is moved to its right-hand position the braking bars are moved inwardly toward the associated rail to their braking` positions in which they engage the sides of the'wheels of a railway vehicle traversing rails 1 and 1a.

The motor M is controlled by three inagnet valves D, E and F. Valve F comprises aplunger 7 provided with an armature 7? and a winding 8. When winding 8 is de energized, plunger 7 rises, and theV righthand end Vof cylinder 5 is then connected with atmosphere through pipe 11 and port 10. lhen winding 8 is energized, however, plunger 7 is moved downwardly, disconnecting` pipe V11 from port 10, and connecting this pipe, through port 9, with a suitable source of fluid pressure not shown in the Serial No. 75,541.

drawing. When winding 8 of valve F is energized, therefore, the fluid pressure supplied to the right-hand end of cylinder 5 moves piston 6 tothe left, thereby moving the braking bars 2, 3, 2EL and 3a away from their braking positions.

Valve E is somewhat similar to Valve F. When winding 8 of this valve is de-en`ergized plunger 7 rises, thereby connecting the lefthand end of cylinder 5 with atmosphere through pipe 12 and port 13. lVhen winding 8 of valve E is energized, however, plunger 7 is moved downwardly to blank pipe 12. Y

Referring now to' valve D, when winding 8 'of this valve is cle-energized, plunger 7 is moved upwardly to blank pipe l2.' When winding 8 of valve D is energized, however, the plunger 7 is moved downwardly, thereby connecting pipe 12, through port 14, with a source of fluid pres ure not shown in the drawing. lt will be plain therefore that when valve E is closed and valve D is open,

fluid pressure is supplied through pipe v12 to the left-hand end of cylinder 5. Piston 6 is then moved to the right, thereby moving the braking bars to their braking positions. When valve D is closed,and valve E is open, however, the left-hand end ofA cylinder 5 is connected with atmosphere.

It is obvious that the brakingl force exerted upon a vehicle by the braking bars depends upon the force with which the piston 6 is moved to the right. @ne feature of my present invention is the provision of means for adjusting the pressure exerted upon the piston 6 and for automatically controlling such pressure. I will now describe the apparatus by means of which I accomplish this result.

The valves D, E and F are control-led in part by a plurality of pressure responsive circuit controllers. These circuit controllers are arranged in two series, the circuit con trollers of one series being designated by the reference characters K'and those of the other bythe reference characters L.V Each of the circuit controllers K comprises a Bourdon tube 15, connected through pipe 17EL withv the left hand end of cylinder 5. Associated with each such Bourdon tube and controlled thereby is a normally closed contact`16 arranged to be opened when the pressure in the left hand end of cylinder 5 'exceeds a predeliz terminedV value. Circuit controllers L are similar to circuit controllers K and each comprises a Bourdon tube 15 connected with a pipe 175 which communicates with the left hand end of cylinder 5. The circuit controllers K and Lv are so adjusted that tor pressures in cylinder 5 below a low value, such as 2O pounds per square inch, all the circuit controllers are closed. As the pressure increases above this low value the circuit controllers ot each series successively open. Y

In the drawing the exponent for each circuit controller designates, in pounds per square inch, the pressure required to open this circuit controller. For example, K2o is arranged to open when the pressure in the left-hand end' ot cylinder 5 exceeds 20 pounds per square inch, circuit cont-roller K40 is arrangedto open when this pressure exceeds a pounds per square inch, circuit controller L25 when the pressure exceeds 25 pounds per square inch, etc. It should be particularly pointed out that with each circuit controller K there is associated a corresponding circuit controller L which opens whenthe pressure rises a small amount above the pressurenecessary to operate such circuit controller K.

The reference character G designates a manually operable selector comprising a lever 18 movable into engagement with any one of an outer row of ixed contacts 22, 24, 26, 28 and 30. The selector also comprises an` inner row of iixed contacts2`1, 23, 25, 27 and 29. The parts are so arranged that when the lever 18 is moved into engagementwith one of the contacts in the outer row, such as contact 22, the lever also engages a corresponding contact of the inner row, such as contact 21. The selector also comprises stillanother fixed contact 19 so located that lever 18 may at times engage-thisl contact.

Contact 22 `is connect-ed with one terminal or'V winding 8 of valvev D through circuit controller K25. Contact 2li is connected with this terminal through circuit controller Kto. Inl similar manner contact-s 25 and 28- are connected with the samel terminal et winding 8fofvalve D through circuit controllers K5@ and K8", respectively. Contact 80 is connected directly with this terminal. Contact 21 is connected,through circuit controller L25", with one terminal ot winding 8 of val-ve E. Similarly, contacts 23, connected, through circuit controllers L25, L55, andL55, respectively', withthe same terminal of this winding. Contact 29 is connected directly with the same terminal of winding 8 ofvalv'e In explaining the operation of theapparatus as a whole I will first-assume that the operator wishesto inalre a slight brake application. He accomplishestliis by moving lever 18 into engagementV withV contacts`A 21 25. and 2? are and 22. Current then flows from terminal B of a suitable source of energy, not shown in the drawing, through lever 18,A contact 21, circuit controller L25, and winding 8 ot' valve E to terminal C of the same source. Valve E is therefore closed, blanling pipe 12. At

the same time current flowsv from lever 18,

through contact 22, circuit controller K25,

circuit controller K2 again closes to admit.

fluid pressure tothe cylinder. It the pressure inthe cylinder tor any reasonl exceeds 25-pounds per square inch, circuitcontroller L25 opens and interrupts the circuit for valve E. Pressure is then exhausted from the cylinder' until the pressure is reduced to 25 pounds per square inch, whereupon the circuit controller L25 again closesyto complete the circuit for valve E. Itwill be apparent thereforethat when lever 18 of selector- G .engages contacts 21 and 22, the.v pressure in the,A leiti-hand-end of cylinder will be maintained between and 25 pounds-per square inch. Similarly, if lever 18 is moved into engagement with contacts-28 and 2li, the pressure in cylinder 5 is maintained between 4.0. and L.t5 pounds per square inch, it' lever 18 engages contacts 25'and 26, the pressure in cylinder 5 is maintained between 60 and `pounds perv square inch, and if lever 18 engagescontacts 2T and28, pressure in cylinder 5 is maintained between 80y and 85 pounds per square inch. It lever 18T is moved-into engagement withlcontacts-29 and 30, windings 8 of valves D andk EI are both energized directly and-'- under these conditions valve E remains' closed andthe entire available pressure-is supplied to cylinder 5.

I will assume-that*itV is desirable to reduce the braking-pressure from a high valuesuch as 6()` poundsr` per squareinch, to; a lower value such for example as 20 tov 25 pounds per square inch. To do this, lever 18 is moved into engagement with contacts 21 and 22. Because ot the. high pressure existing in-cylinder 5 circuit controllers K20 and L25 are both open soV that the circuits for valves D and E areboth open. Fluid pressure is therefore exhausted through valve E unt-il the pressure in cylinder 5` is reduced below-25 pounds per square inch. Circuit controller L25 thereupon closes, compl-etingthe -circuit for valve E andA preventing further reduction in cylinder 5. The

pressure is then maintained between 20 pounds and 25 pounds per square inch as already explained.

If the operator wishes to restore the braking bars to their non-braking positions, he

moves lever 18 into engagement with contact 19. Current then flows from terminal B, through lever 18, contact 19, and winding 8 of valve F, to terminal C. Plunger 7 of valve F therefore moves downwardly and fluid pressure is admitted to the right-hand end of cylinder 5. The circuits for valves D and E are now open so valve D is closed and valve E is open to exhaust the left-hand end of cylinder 5 to atmosphere. Piston G therefore moves to the left and drives the braking bars to their non-braking positions. rlhe lever 18 may then be returned to the position in which it is illustrated in the drawing wherein the circuits for all of the valves D, E and F are open.

I do not claim as my invention the conibination of a plurality of pressure responsive devices subjected to the pressure in the operating cylinder and in turn actuating a plurality of circuit controllers for governing the valve which admits fluid pressure to said cylinder, such combination beingthe invention of John P. Coleman and disclosed and claimed by him in an application for Letters Patent of the United States, filed pril 26, 1926, Serial No. 1O1l,566, fo rails way braking apparatus.

Although I have herein shown and described only one form of railway braking apparatus embodying my invention, it is understood that various changes and modifications ni ay be made therein within the scope; of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention what I claim is: Y Y

1. Railway braking apparatus comprising a braking bar located in the trackway, a fluid pressure motor for operating said bar, a first valve for admitting fluid pressure to said motor, a second valve for exhausting pressure from said motor, and two circuit controllers both responsive to the pressure in said motor and each controllingl one of said valves.

2. Railway braking apparatus comprising a braking bar located in the trackway, a fluid pressure motor for operating said bar, a first valve for admitting fluid pressure to said motor, a secon-d valve for exhausting pressure from said motor, a first series of circuit controllers arranged to be succes sively operated as the pressure in said motor increases, a second series or" circuit controllers arranged to be successively operated as the pressure in said motor increases, and manually operable means for controlling said first valve by any selected one of said first series of circuit controllers and for simultaneously controlling said second valve by a corresponding circuit controller of said second series.

3. Railway braking apparatus comprising a braking bar located in the trackway, a fluid pressure motor for operating said bar, a first magnet valve for admitting fluid pressure to said motor, a second magnet valve for exhausting 'fluid pressure from said motor, two series of circuit controllers the circuit controllers of each series beingsuccessively operated as the pressure in said motor increases, and means for connecting said first valve in series with a selected oircuit controller of one series and for simultaneously connecting said second valve in series with a corresp-onding circuit controller of the other series.

t. Railway braking apparatus comprising a braking bar located in the trackway, a fluid pressure motor for operating saidbar, two circuit controllers responsive to the pressure in said motor and arranged to be operated at different values of said pressure, a first valve for admitting fluid pressure to said motor, a second valve for exhausting fluid pressure from said motor, and means for simultaneously controlling said first valve by one of said circuit controllers and said second valve by the other said circuitcontrollers.

5. Railway braking apparatus comprising a braking bar located in the trackway, a

fluid pressure motor for operating said bar, two series of circuit controllers responsive to the pressure in said motor and the individual circuit controllers of each series being arranged to operate successively as the pressure in said motor increases, a Erst magnet valve arranged when energize-d to admit fluid pressure to said motor, a second magnet valve arranged when cle-energized to connect said motor with atmosphere, and means for connecting any selected circuit controller of one series with said first valve, and for simultaneously connecting said second valve with a corresponding circuit controller of the other series.

6. Railway braking apparatus comprising a braking bar located in the trackway, a fluid pressure motor for operating said bar, two series of normally closed circuit controllers responsive to the pressure in said motor and the individual circuit controllers of each series being arranged to open successively as the pressure in said motor increases, a first magnet valve arranged when energized to admit fluid pressure to said motor, a second magnet valve arranged when de-en- -ergized to connect said motor with atmosphere,.and means for connecting any selected circuit controller of one series with said first valve, and for simultaneously connecting said second valve with a corresponding circuit controller of the other series.

7. Railway braking apparatus comprising a braking bar located in the trackway7 a `fluid pressure motor for operating said bar, tWo normally closed circuit controllers responsive to the pressure in said motor and arranged to open at different. values of' said pressure, a normally closed magnet valve arranged Whenenergized to admit fluid pressure to said motor, a normally openmagn-et valve arranged when energized to disconnect saidv motor from atmosphere, and means for connecting said circuit controllers in series with said two magnet valves respectively'.

8. Railway braking apparatus comprising a brakingI bar located in the trackway, a fluid pressure motor for operating said bar, two normally closed circuit controllers responsive to the pressure in said motor and one arranged to open When such pressure en ceedsV one predetermined value and the other arranged to open when such pressure exceeds a higher predetermined value,V means controlled by said one circuit controller for admitting` fluid pressure to the motor, and means controlledby the other said circuit controller for exhausting fluid pressure from the motor.

9. Railwayv braking apparatus comprising al braking bar located in the traclzivay, a fluidpressure motor for operating said bar, a first series of circuit controllers arranged to be operated successively as the pressure in said motor incr-eases, a second series of circuit controllers each of Which is arranged to`operate` when the pressure in saidlmotor exceeds a slightly higher value than that necessary to operate the corresponding circuit controller of the rst series, a lirst magnet valve for admitting fluid pressure to said motor, a second magnet valve for exhausting Huid pressure from said motor, and means tor'controlling said first valve by any selected circuit controller of said first series and for simultaneously controlling said second' valve by ther corresponding circuit controller of the second series.

l0. Railway braking apparatus comprising a braking bar located in the trackway,

a cylinder containing a reciprocable piston operatively connected with said bar, a first magnet valve arranged When energized to supply fluid pressure to one end of saidcylinder and when cle-energized to connect such end of the cylinder with atmosphere, a second magnet valve arranged when energized to admit fluid pressure to the other end of said cylinder and when cle-energized to interrupt such admission, a third magnet valve arranged when de-energized to conn-ect such other end of the cylinder With atmosphere and When energized to interrupt such connection, a irst series of normally closed circuit controllers responsive to the pressure in said other end ol' the cylinder and arranged to be successively opened as such pressure increases, a second series of normally closed circuit controllers also responsive to the pressure in saidvother end of the cylinder and arranged to be successively opened as such pressure increases, each cir#- cuit controller of said second series being arranged to open when the pressure in such other .end of the cylinder exceeds by a slight amount the value necessary to operatethe corresponding circuit controller of said first series, and a selector for at times supplying current to said first magnet valve and for at other times supplying current to said second.

magnet' valve over a selected circuit controller of said first series and for simultaneously supplying curr-ent to said third magnet valve over the corresponding circuit controller of said secondseries.

In testimony whereof I a-flix my signature.

LLOYD Vi LEWI S'. 

